1. Field of the Invention
This invention is related to radio navigation systems using satellites. To be more precise, it is related to satellite-based position-determining systems which use satellites for determining the position of aircraft, automobile, ship, building and the like in movement or at a standstill on or near the earth's surface.
2. Description of the Prior Art
Various methods are known for determining the geographical position of aircraft, ship and the like. With the advance of space technology, systems using artificial satellites have been introduced recently. These systems have superior features over other types of system, such as insusceptibility to influences of the topography because the signal to be received comes from the sky. Of various position determining systems using satellites and proposed in the past, important systems are summarized here.